HPLC-MS/MS法测定大鼠血浆中芬太尼浓度及其代谢机制研究

目的:建立以高效液相色谱-质谱(HPLC-MS/MS)法测定大鼠血浆中芬太尼浓度的方法,并研究肝脏对芬太尼代谢的影响。方法:以氨基比林为内标,采用正己烷提取处理血浆样品;色谱柱为InertsilODS-3,流动相为甲醇-0.5%甲酸溶液(90∶10);将大鼠分为正常对照组和无肝期组(夹闭肝门),静脉注射芬太尼20μg·kg-1,考察给药后1、2、3、5、10、15、20、30、45、60、75、90min芬太尼血药浓度的变化及其药动学情况。结果:芬太尼、氨基比林与血浆中内源性杂质分离良好;芬太尼检测浓度的线性范围为0.5～400ng·mL-1(r=0.9997),平均回收率为96.90%～102.32%,日内和日间RSD均小于10.56%。与正常对照组比较,无肝期组芬太尼浓度下降明显减慢,AUC0～(P<0.05)、t1、Cmax均增加。结论:肝脏是芬太尼的主要代谢器官,但也存在肝外代谢。t/2z所建立的方法可用于大鼠体内芬太尼的含量测定。

Content Determination of Fentanyl in Rat Plasma by HPLC-MS/MS and Metabolic Mechanism Study

OBJECTIVE： To develop HPLC-MS/MS method for the content determination of fentanyl in rat plasma and to investigate the effect of liver tissue on metabolism of fentanyl. METHODS： The plasma samples were extracted by hexane using aminophenazone as internal standard. The separation was carried out on an Inertsil ODS-3 column with mobile phase consisted of methol-0.5%fomic acid （90 ∶ 10）. The rats were randomly divided into normal control group and anhepatic phase group （occlusion of hepatic portal）. Both groups were injected with fentanyl 20 μg·kg-1 （i.v.）. The plasma concentrations and pharmacokinetics of fentanyl were investigated 1, 2, 3, 5, 10, 15, 20, 30, 45, 60, 75, 90 min after medication. RESULTS： Fentanyl and aminopyrine were well-separated from endogenous impurity of plasma. The linear range of fentanyl was 0.5～400 ng·mL-1 （r=0.999 7） with an average recovery of 96.90%～102.32%. RSD of intra-day and inter-day were both less than 10.56%. versus the normal control group, the reduction of fentanyl concentration in anhepatic phase group was more slowly, pharmacokinetic parameters of fentanyl were increased, such as AUC0～t（P〈0.05）, t1/2z, Cmax. CONCLUSION： Metabolism of fentanyl is mainly operated in liver while extrahepatic metabolism is also performed. The method is suitable for content determination of fentanyl in rat plasma.